I'm after a bit of advice / info... I can ask this question to customer services, but I'm not confident of them knowing so thought maybe someone on here may have experience.

After contracting for years, lots of different addresses through moving and not much credit, I've got to the point where I've been in a permanent job and one house for a couple of years, and I'm building a credit history. My oldest open account is my Three One Plan SIM which has been running for just over 3 years. This really has a good impact on my credit files and something that for me is worth keeping at £18 a month for the short term (the next newest account is just under 2 years old). My better half may move to using this SIM / line if I keep it too, so it is worth keeping.

I've just taken out a new iPhone with Three. I took out the iPhone first with the view of seeing what happened to my credit file - if it was reported as the same account or a separate one - and as you might expect, a new account was opened.

Now with the imminent Three One Plan switch-off, I'm wondering if I change plan will it be deemed as the old contract ending and a new one starting - and if it will be reported as a new account to the credit reference agencies? If so, I may just get rid of it. If however they keep it going as the same account and reported as such to the credit reference agencies, then it's worth me holding onto for a while.

I was under the impression you only get credit checked if you take out a new deal or if you upgrade to a phone contract. I didn't think they would recheck you as you change plan on SIM only.

When you upgrade or change plan, your account and phone number remain the same so it should still be reported on the same account to the CRA

If you buy an additional line this is treated as a separate account which is why it shows as a separate account on the CRA reports.

To be perfectly honest the impact on your credit file of closing down a mobile account would be minimal. It could also be viewed as a plus as the account status would change to settled and having a number of successfully settled accounts can be of benefit too

Thanks both for the replies.

carguy143 - Yup, I know there won't be a another credit check, it's more how the account will be reported.

davethorp - Having moved lots, I have a fair few settled accounts already for utilities and things so they're considered a "good" factor. The age of your oldest open account I have always been led to believe is another factor, with the longer the better? If it's reported as the same account though (which would make sense) then that'd be great.

Thinking about it a bit more, either way I'm going to have to change it so I may as well change it to another 30 day rolling SIM. Worst case, it gets reported as a new account and I close it... Best case is that it's reported as the same and I switch it to a 12 month rolling SIM to reduce the cost.

Having accounts open longer does show stability. But most credit checking applications are more concerned about stability with your bank account. Which is why the vast majority ask how long have you had your bank account. And is also why I keep my natwest account I opened in 2006 open despite having much better accounts elsewhere now